Light from a He-Cd laser \((\lambda=442 \mathrm{~nm})\) passing through a two-slit diffraction grating forms a pattern on a screen \(2.0 \mathrm{~m}\) away from the grating. If the first bright fringe is located at a linear distance \(y=22.1 \mathrm{~mm}\) to the left of the central bright fringe, what is the slit spacing? What is the position of the second dark fringe?